I am trying to create a VPN server on a Mac at my school (I'm a teacher) so I can access the network from home and print to our document server. I see how to connect to a VPN server from a Mac, but not how to set up a VPN server.
You shouldn't be setting up a VPN server on your school's network, the school should already have a VPN in place. Most likely they'll provide you with a client to connect with, and logon info. Once you log on, it's as if your machine is on the school network directly, and you can simply log into your mac or any other file server and transfer files as you need.